Detention of Children without due cause

[Samgurney88]

I am aware that the laws surrounding detention (at school) require that behaviour was poor, yet there are different views on what conduct would be classified as poor. I am aware that there are a number of reason why a guardian can object to a detenetion, but it is not clear if it can be objected to on the grounds of there is despute as weather the childs conduct was poor.
My name is Sam, I'm a 14 year old school student. My maths teacher has required that the entire class stay behind on Monday afternoons, so she can conduct her 'revision sessions'. I appreciate this is in the best of our interest, but the opportunity for any of us to object has not been provided. Many of us do not concent to being detained, without a justifiable reason. However, should my Teacher be found wrong on the matter of not allowing the children the opportunuity to either concent or disapprove of the sessions, she would then be able to issue the entire class a detention, in order to attend her seesions. Would this be legal, in the respect she would have no just reason to suggest that our behaviour and conduct warranted a detention?